Search

Background: Buffered crystalloid solutions are increasingly recommended as first-line intravenous resuscitation fluids. However, guidelines do not distinguish between the different types of buffered solutions. The aim of this scoping review was to assess the evidence on the use of lactate- vs acetate-buffered crystalloid solutions and their potential benefits and harms., Methods: We conducted this scoping review in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses Extension for Scoping Reviews. We searched PubMed, Embase, Epistemonikos, and the Cochrane Library for studies assessing the effect of lactate- vs acetate-buffered crystalloid solutions on any outcome in adult hospitalised patients. The quality of evidence was assessed using the Grading of Recommendations Assessment, Development and Evaluation approach., Results: We included a total of 29 studies, 25 of which were clinical trials and four were observational studies. Most studies were conducted in surgical settings and indications for use were poorly described. The most commonly administered solutions were Ringer's lactate vs Ringer's acetate or Plasma-Lyte™. Outcomes included acid/base and electrolyte status; haemodynamic variables; and markers of renal and liver function, metabolism, and coagulation. Only a few studies reported patient-centred outcomes. Overall, the data provided no firm evidence for benefit or harm of either solution, and the quantity and quality of evidence were low., Conclusions: The quantity and quality of evidence on the use of different buffered crystalloid intravenous solutions were low, data were derived primarily from surgical settings, and patient-important outcomes were rarely reported; thus, the balance between benefits and harms between these solutions is largely unknown., (Copyright © 2020 British Journal of Anaesthesia. Published by Elsevier Ltd. All rights reserved.)

Since 1968, when Baxter and Shires developed the Parkland formula, little progress has been made in the field of fluid therapy for burn resuscitation, despite advances in haemodynamic monitoring, establishment of the 'goal-directed therapy' concept, and the development of new colloid and crystalloid solutions. Burn patients receive a larger amount of fluids in the first hours than any other trauma patients. Initial resuscitation is based on crystalloids because of the increased capillary permeability occurring during the first 24 h. After that time, some colloids, but not all, are accepted. Since the emergence of the Pharmacovigilance Risk Assessment Committee alert from the European Medicines Agency concerning hydroxyethyl starches, solutions containing this component are not recommended for burns. But the question is: what do we really know about fluid resuscitation in burns? To provide an answer, we carried out a non-systematic review to clarify how to quantify the amount of fluids needed, what the current evidence says about the available solutions, and which solution is the most appropriate for burn patients based on the available knowledge., (© The Author 2016. Published by Oxford University Press on behalf of the British Journal of Anaesthesia. All rights reserved. For Permissions, please email: journals.permissions@oup.com.)

Background: Variation in clinical practice in the perioperative environment and intensive care unit is a major challenge facing modern medicine. The objective of the present study was to analyse intraoperative crystalloid administration practices at two academic medical centres in the USA., Methods: We extracted clinical data from patients undergoing intra-abdominal procedures performed at UC Irvine (UCI) and Vanderbilt University (VU) Medical Centres. Limiting data to uncomplicated elective surgery with minimal blood loss, we quantified variability in fluid administration within individual providers, between providers, and between types of procedures using a corrected coefficient of variation (cCOV). Regression was performed using a general linear model to determine factors most predictive of fluid administration., Results: For provider analysis and model building, 1327 UCI and 4585 VU patients were used. The average corrected crystalloid infusion rate across all providers at both institutions was 7.1 (sd 4.9) ml kg(-1) h(-1), an overall cCOV of 70%. Individual providers ranged from 2.3 (sd 3.7) to 14 (sd 10) ml kg(-1) h(-1). The final regression model strongly favoured personnel as predictors over other patient predictors., Conclusions: Wide variability in crystalloid administration was observed both within and between individual anaesthesia providers, which might contribute to variability in surgical outcomes., (© The Author 2015. Published by Oxford University Press on behalf of the British Journal of Anaesthesia. All rights reserved. For Permissions, please email: journals.permissions@oup.com.)

Background: Several different crystalloid solutions are available for i.v. fluid administration but there is little information about their specific advantages and disadvantages., Methods: We performed a systematic search of MEDLINE, EMBASE, and CENTRAL up until May 17, 2012, selecting all prospective human studies that directly compared any near-isotonic crystalloids and reported any outcome., Results: From the 5060 articles retrieved in the search, only 28 met the selection criteria. There was considerable heterogeneity among the studies. Several articles reported an increased incidence of hyperchloraemic acidosis with the use of normal saline, and others an increase in blood lactate levels when large amounts of Ringer's lactate solutions were infused. From the limited data available, normal saline administration appears to be associated with increased blood loss and greater red blood cell transfusion volumes in high-risk populations compared to Ringer's lactate. Possible effects of the different solutions on renal function, inflammatory response, temperature, hepatic function, glucose metabolism, and splanchnic perfusion are also reported. The haemodynamic profiles of all the solutions were similar., Conclusions: Different solutions have different effects on acid-base status, electrolyte levels, coagulation, renal, and hepatic function. Whether these differences have clinical consequences remains unclear., (© The Author [2014]. Published by Oxford University Press on behalf of the British Journal of Anaesthesia. All rights reserved. For Permissions, please email: journals.permissions@oup.com.)

Background: The optimal resuscitation fluid for the early treatment of severe bleeding patients remains highly debated. The objective of this experimental study was to compare the rapidity of shock reversal with lactated Ringer (LR) or hydroxyethyl starch (HES) 130/0.4 at the early phase of controlled haemorrhagic shock. To assess the influence of vascular permeability in this model, we measured plasma vascular endothelial growth factor (VEGF) levels during the experiment., Methods: Thirty-six anaesthetized and mechanically ventilated piglets were bled (<30 ml kg(-1)) to hold mean arterial pressure (MAP) at 40 mm Hg for more than 30 min and were resuscitated in two randomized groups: LR (n=14) or HES (n=14) at 1 ml kg(-1) min(-1) until MAP reached its baseline value of ±10%. MAP was maintained at its baseline value for 1 h. The time and fluid volume necessary to restore the baseline MAP value were measured., Results: The time to restore the baseline MAP value of ±10% was significantly lower in the HES group (P<0.001). During the initial resuscitation phase, the infused volume was 279 (119) ml in the HES group and 1011 (561) ml in the LR group (P<0.0001). During the stabilization phase, the infused volume was 119 (124) ml in the HES group and 541 (506) ml in the LR group. Biological data and plasma VEGF levels were similar between the groups., Conclusions: Restoration of MAP was four times faster with HES than with LR in the early phase of controlled haemorrhagic shock. However, there was no evidence of increased vascular permeability., (© The Author [2013]. Published by Oxford University Press on behalf of the British Journal of Anaesthesia. All rights reserved. For Permissions, please email: journals.permissions@oup.com.)

Background: Goal-directed fluid therapy has been shown to improve outcomes after colorectal surgery, but the optimal type of i.v. fluid to use is yet to be established. Theoretical advantages of using hydroxyethyl starch (HES) for goal-directed therapy include a reduction in the total volume of fluid required, resulting in less tissue oedema. Recent work has demonstrated that new generations of HES have a good safety profile, but their routine use in the perioperative setting has not been demonstrated to confer outcome benefit., Methods: We randomly assigned 202 medium to high-risk patients undergoing elective colorectal surgery to receive either balanced 6% HES (130/0.4, Volulyte) or balanced crystalloid (Hartmann's solution) as haemodynamic optimization fluid. The primary outcome measure was the incidence of gastrointestinal (GI) morbidity on postoperative day 5. Secondary outcome measures included the incidence of postoperative complications, hospital length of stay, and the effect of trial fluids on coagulation and inflammation., Results: No difference was seen in the number of patients who suffered GI morbidity on postoperative day 5 [30% in the HES group vs 32% in the crystalloid group; adjusted odds ratio=0.96 (0.52-1.77)]. Subjects in the crystalloid group received more fluid [median (inter-quartile ranges) 3175 (2000-3700) vs 1875 (1500-3000) ml, P<0.001] and had a higher 24 h fluid balance [+4226 (3251-5779) vs +3610 (2443-4519) ml, P<0.001]. No difference in the incidence of postoperative complications was seen between the groups., Conclusions: Goal-directed fluid therapy is possible with either crystalloid or HES. There is no evidence of a benefit in using HES over crystalloid, despite its use resulting in a lower 24 h fluid balance.

Background: Controversy exists regarding the optimal i.v. fluids for use with a goal-directed haemodynamic algorithm., Methods: In a double-blind pilot study, we randomly assigned 50 patients with primary ovarian cancer undergoing cytoreductive surgery to receive either balanced crystalloid or balanced starch (HES, 130/0.4, 6%) solutions up to the dose limit (50 ml kg(-1)). Fluids were administered to optimize stroke volume measured by oesophageal Doppler within a goal-directed haemodynamic algorithm., Results: Baseline subject characteristics were similar in both groups. The balanced HES solution maintained stroke volume (P=0.012) better with administration of less fluid. Subjects in the colloid group reached the dose limits of the study medication less frequently (92% vs 62%, P=0.036) and later (2:26 vs 3:33 h, P=0.006) and also required less transfusion of fresh-frozen plasma units (6.0 vs 3.5 units, P=0.035) compared with the crystalloid group. Intra- and postoperative urine output and perioperative plasma levels of creatinine and neutrophil gelatinase-associated lipocalin as renal injury marker were similar in both groups. No differences in the length of intensive care unit and hospital stay were found., Conclusions: Using a goal-directed haemodynamic algorithm to optimize stroke volume, a balanced HES solution is associated with better haemodynamic stability and reduced need for fresh-frozen plasma. There were no signs of renal impairment by colloid solutions when fluid administration is targeted to optimize cardiac preload.

Background: This study tested the circulatory effectiveness of post-trauma administration of a large intravascular volume expander, hydroxyethyl starch 130/0.4 (HES), vs standard lactated Ringer's solution (RL)., Methods: Liver injury was inflicted in 14 pigs [31 (4) kg; mean (sd)] and treatment simulated an acute pre-hospital event: after a standard first-respond delay (7 min), volume administration was provided in three phases to simulate increasing intravascular access. In the first two phases, the fluid was administered either by HES or by RL and, during the last phase, all animals received HES to stabilize the intravascular volume., Results: The liver trauma severed an equal number of 1-3 mm diameter blood vessels [1.4 (0.6)] and after 7 min, the blood loss was 184 (127) ml and mean arterial pressure had decreased by 19 (13) mm Hg (P<0.01). The intravascular volume expansion effect was 115 (25)% for HES and 76 (21)% for RL (P<0.05), yet oxygen uptake was maintained in zero of seven vs three of seven pigs and the survival was three of seven vs seven of seven, respectively (P<0.05). In these animals, the initial administration of HES provoked uncontrolled bleeding, whereas the administration of RL was associated with attenuated bleeding: total blood loss 2455 (1919) vs 311 (208) ml, respectively (P<0.01), reflecting that bleeding ceased in six of the pigs administered RL., Conclusions: After injury, the intravascular volume expanding effect of HES was larger than that for RL. However, initial administration of HES provoked uncontrolled haemorrhage, suggesting that prioritizing intravascular volume expansion did not result in stabilization of the circulation after haemorrhage.

Background: Information is lacking concerning optimal infusion rates of crystalloid during resuscitation from acute haemorrhage. In this study, a mathematical model was used to predict infusion volume of crystalloid needed to restore and maintain blood volume after acute haemorrhage., Methods: The scenario was a haemorrhage of 15 ml kg(-1) over 30 min in a 70 kg man. A bolus of crystalloid was administered at a rate of 40, 60, 80, 100, or 120 ml kg(-1) h(-1) until blood volume was restored. Fluid infusion rate needed to maintain blood volume for a further 1 h was computed., Results: Blood volume was restored earlier at high bolus infusion rates compared with low bolus infusion rates (6 min at 120 ml kg(-1) h(-1) vs 63 min at 40 ml kg(-1) h(-1)). Fluid infusion rates for blood volume maintenance approached 33 ml kg(-1) h(-1) irrespective of bolus infusion rates. The restoration fluid volume at 40 ml kg(-1) h(-1) was 2.9 litre, three times that at 80-120 ml kg(-1) h(-1). The maintenance fluid volume at 80-120 ml kg(-1) h(-1) was 2.9 litre, 0.6 litre more than that at 40 ml kg(-1) h(-1). During the blood volume maintenance, the interstitial volume increased to 3.8 litre above normal at 40 ml kg(-1) h(-1) and to 2.5 litre at 80-120 ml kg(-1) h(-1)., Conclusions: Bolus crystalloid infusion exceeding 80 ml kg(-1) h(-1) may not increase effectiveness of fluid resuscitation. Crystalloid resuscitation for more than 2 h may be detrimental in view of an excessive net fluid retention.

Background: Tissue tolerance to oxygen privation during acute normovolaemic haemodilution with different fluids remains unclear. We tested the hypothesis that hydroxyethyl starch (HES) is superior to lactated Ringer's solution in pigs for preserving tissue perfusion during acute normovolaemic haemodilution., Methods: Twenty-four animals were randomized into control, lactated Ringer's solution and HES groups. All groups, except the control, underwent acute normovolaemic haemodilution. Haemodynamics, oxygen parameter indices, global anaerobic metabolic markers, echocardiographic parameters, gastric tonometry and serum osmolarity were monitored at baseline, immediately after (0 min) and 60 and 120 min after the end of haemodilution. Myocardial, liver, stomach and intestine samples were collected for further evaluation., Results: Cardiac and oxygen parameter index responses to acute normovolaemic haemodilution were comparable. However, the increment in cardiac index, stroke volume index, and left ventricular stroke work index were more sustained in the starch group. In the lactated Ringer's group, gastric pH decreased significantly and was accompanied by a significant increase in lactate. Myocardial ultrastructure was better preserved in the starch group. The other tissue samples presented no change., Conclusions: In this model of ANH, the starch group had a superior haemodynamic response. Minor loss of myocardial cellular integrity and preserved gastric pHi reinforce these findings.

Objectives: To evaluate the effects on intestinal oxygen supply, and mucosal tissue oxygen tension during haemorrhage and after fluid resuscitation with either blood (B; n=7), gelatine (G; n=8), or lactated Ringer's solution (R; n=8) in an autoperfused, innervated jejunal segment in anaesthetized pigs., Methods: To induce haemorrhagic shock, 50% of calculated blood volume was withdrawn. Systemic haemodynamics, mesenteric venous and systemic acid-base and blood gas variables, and lactate measurements were recorded. A flowmeter was used for measuring mesenteric arterial blood flow. Mucosal tissue oxygen tension (PO(2)muc), jejunal microvascular haemoglobin oxygen saturation (HbO(2)) and microvascular blood flow were measured. Measurements were performed at baseline, after haemorrhage and at four 20 min intervals after fluid resuscitation. After haemorrhage, animals were retransfused with blood, gelatine or lactated Ringer's solution until baseline pulmonary capillary wedge pressure was reached., Results: After resuscitation, no significant differences in macrohaemodynamic parameters were observed between groups. Systemic and intestinal lactate concentration was significantly increased in animals receiving lactated Ringer's solution [5.6 (1.1) vs 3.3 (1.1) mmol litre(-1); 5.6 (1.1) vs 3.3 (1.2) mmol litre(-1)]. Oxygen supply to the intestine was impaired in animals receiving lactated Ringer's solution when compared with animals receiving blood. Blood and gelatine resuscitation resulted in higher HbO(2) than with lactated Ringer's resuscitation after haemorrhagic shock [B, 43.8 (10.4)%; G, 34.6 (9.4)%; R, 28.0 (9.3)%]. PO(2)muc was better preserved with gelatine resuscitation when compared with lactated Ringer's or blood resuscitation [20.0 (8.8) vs 13.8 (7.1) mm Hg, 15.2 (7.2) mm Hg, respectively]., Conclusion: Blood or gelatine infusion improves mucosal tissue oxygenation of the porcine jejunum after severe haemorrhage when compared with lactated Ringer's solution.

We studied 160 patients undergoing elective Caesarean section under spinal anaesthesia who received a preloading volume of 15 ml kg-1 of 10% pentastarch in 0.9% saline, or Hartmann's solution, in a prospective, randomized, double-blind study. We compared the incidence of spinal-induced hypotension in each group. Hypotension was defined as a decrease in systolic arterial pressure to less than 70% of baseline values or < or = 90 mm Hg, whichever was the greater. The groups were comparable in physical characteristics and there was no serious morbidity. Fetal outcome was similar in both groups. Significantly more patients in the Hartmann's group (n = 38, 47.5%) developed hypotension than in the pentastarch group (n = 10, 12.5%) (P < 0.0001). Linear regression analysis showed that the only significant variable was type of fluid used. Blood glucose concentrations were not related to the presence of hypotension. We conclude that starches may be suitable for preloading in Caesarean section under spinal anaesthesia and provide an alternative to the aggressive use of vasoconstrictors.

We have studied the effects of randomized preloading with either a crystalloid (lactated Ringer's) 15 ml kg-1 or colloid (hydroxyethyl starch) 7.5 ml kg-1 solution in 20 parturients undergoing elective Caesarean section under extradural anaesthesia, on blood flow in maternal placental and non-placental uterine and placental arcuate arteries and in fetal umbilical, renal and middle cerebral arteries, using a pulsed colour Doppler technique. Simultaneously, fetal and neonatal myocardial function were investigated by pulsed Doppler and M-mode echocardiography. We found no changes in maternal or fetal blood velocity waveform indices after crystalloid preloading, but the pulsatility index of the maternal non-placental uterine artery increased significantly after colloid preloading. Fetal heart rate decreased after preloading with crystalloid solution. There were no differences in fetal or neonatal myocardial function between the groups, and the outcome of the newborn infants were uneventful in all cases. These results suggest that preloading with either a crystalloid or colloid solution may lead to different uterine and fetal haemodynamics but these solutions had only minimal effects on fetal and neonatal myocardial performance and no effect on the clinical condition of newborns in uncomplicated pregnancies.